Accelerated Partial Breast Irradiation (APBI)

For selected patients with low risk disease, they have the option of accelerated partial breast irradiation. In this procedure, a smaller volume of breast tissue around the original tumour location only is irradiated. This allow the treatment to proceed at a faster pace, shortening what used to take 4-6 weeks to just 1 week or even to a single fraction.

Evidence for this APBI is increasing in recent years with the publication of medium term results from randomized clinical trials. Long terms results are available from single institution experience as well

Careful selection of patients is extremely important. Various professional bodies have published recommended selection criteria. In general, suitable patients are usually older (age >45 years), with unifocal tumours of about 2-3cm in diameter, and which have been excised with clear margins and no nodal involvement by conventional nodal staging procedures.

Some of these APBI techniques is illustrated below.

Intrabeam: Miniaturized linear accelerator with various spherical applicators


Steps in Intrabeam APBI: 1. selecting the right size applicator after performing breast conserving surgery. 2. Apposing cavity wall to applicator. 3. Attaching to x-ray source. 4. Irradiation.


  • Multicatheter Brachytherapy

Inserting multiple flexible catheters across the excision cavity

Completed array of interstitial catheters ready for planning and treatment

Patient undergoing treatment with multiple implanted interstitial catheters


  • Mammosite


  • External Beam APBI

External beam APBI